# GitPython environment-variable exfiltration in Repo.clone_from()

Source: https://junglewise.ai/threats/gitpython-environment-variable-exfiltration-in-repo-clone-from-7a5754b1  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-01. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

Severity: high · CVSS 7.5 · Published 2026-08-01

GitPython is a widely-used library for programmatically interacting with Git repositories. When an application uses the Repo.clone_from() method to clone a repository from a URL supplied by an untrusted source (such as a CI/CD pipeline or dependency scanner), the URL is processed through a function that expands environment variables embedded in the URL. An attacker can craft a malicious URL containing environment-variable tokens (e.g., $AWS_SECRET_ACCESS_KEY) that are automatically replaced with their actual values before the clone attempt. This causes sensitive credentials to be transmitted over the network to an attacker-controlled server, exposing secrets with no user interaction or additional preconditions required.

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** High severity, with a CVSS score of 7.5, published 1 August 2026.

**Which products and versions are affected?** GitPython GitPython <= 3.1.51.

**Is there a fix for This vulnerability?** A patch was published on 2026-07-16: Version 3.1.52 contains the fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is This vulnerability attacked?** It is attacked over the network, in a software library.

**Am I affected?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a credential exposure flaw (CWE-200) in the Git.polish_url() method, a local-path normalization helper that is unconditionally applied to remote clone URLs. On non-Cygwin platforms, polish_url() calls os.path.expandvars() on the input URL, which substitutes $NAME and ${NAME} tokens with the corresponding environment-variable values from the hosting process. An attacker controlling the URL argument to Repo.clone_from() (as in "import repository from URL" features of CI servers, mirrors, and scanners) can embed such tokens; the expanded URL—now containing the literal secret—is passed to the git clone subprocess, which transmits it to the attacker-named host via HTTP(S) or DNS. The unsafe-protocol filter runs before expansion, allowing an attacker with environment-variable write access to additionally bypass protocol restrictions. GitPython 3.1.52 and later patch this by removing or restricting environment-variable expansion on remote URLs. No attack preconditions beyond the ability to supply a clone URL are required; no user interaction is necessary.

## Affected products

- GitPython GitPython <= 3.1.51

## Timeline

- 2026-07-16: disclosed
- 2026-08-01: advisory
- 2026-07-16: patched: Version 3.1.52 contains the fix
- 2026-09-08: other: Duplicate advisory GHSA-m4f3-g4cq-hqrx withdrawn in favor of primary GHSA-rwj8-pgh3-r573

## References

- [https://github.com/gitpython-developers/GitPython/security/advisories/GHSA-rwj8-pgh3-r573](https://github.com/gitpython-developers/GitPython/security/advisories/GHSA-rwj8-pgh3-r573)
- [https://www.vulncheck.com/advisories/gitpython-before-environment-variable-exfiltration-via-clone-from](https://www.vulncheck.com/advisories/gitpython-before-environment-variable-exfiltration-via-clone-from)